The pursuit for fuel alternatives to conventional fossil fuels is primarily driven by the need for a ‘clean’ emissions fuel coupled with low production costs and wide availability. Much attention is paid to the environmental impact of fuel emissions. Research into alternative fuels focuses on fuels that will reduce the amount of particulate matter and oxides produced by fuel combustion as well as fuels that reduce the non-combusted fuel and CO2 emissions and other products of combustion.
The drive for environmentally friendly fuel compositions for transport applications has focused on ethanol. Bio-materials such as organic plant matter can be converted into ethanol, and ethanol produced by such processes has been used as a partial replacement of fuels for spark ignition engines. Whilst this reduces the reliance on non-renewable resources for fuels, the environmental outcomes arising from the use of these fuels in engines has not been substantially improved in an overall sense, with cleaner combustion being offset by continuing use of such fuels in lower efficiency spark ignition engines, and negative environmental impact associated with the use of energy, arable land, fertilisers and irrigation water to create fuel.
Other fuel alternatives for complete or partial replacement of traditional fuels have not become widely used.
One major disadvantage with the complete replacement of traditional fuels, and in particular fuels for compression ignition engines (diesel fuels), with a renewable replacement fuel, relates to the perceived problems associated with the low cetane index of such fuels. Such fuels present problems for achieving ignition in the manner required for efficient operation of the engine.
The present applicants have also recognised that in some remote locations or environments, water is a scarce resource, and in such locations there can be a demand for power generation (such as through diesel engine electricity generation) coupled with water by-product capture for re-use in the local community. In addition moving bulk energy via liquid pipeline is a long standing and cost effective technique for moving large quantities of energy over long distances with minimum visual impact, compared to overhead transmission lines.
The present applicants have also recognised a need in some locations for heat generated in such industrial processes to be captured and re-used in the local community. In some instances this need is coupled to the need for water capture for reuse, referred to above.
In summary, there is a continuing need for alternative fuels for use in internal combustion engines. Fuels that can reduce emissions are of interest, particularly where the improved emissions profile is obtained without a major adverse impact on fuel efficiency and/or engine performance. There is also a need for methods of powering compression ignition engines that enable such engines to be run on diesel replacement fuels containing components not traditionally thought to be suitable for use in such applications. There is additionally a need for diesel engine fuels and engine operation methods that are suited to use in remote locations, or in environmentally sensitive environments (such as in high latitude marine environments particularly in port areas in terms of emissions) or other areas such as remote dry but cold inland areas that can make maximum use of all by-products of the engine operation, including, for example, the heat and water by-products. These objectives are preferably addressed with as little as possible penalty to fuel efficiency and engine performance.